It is proven that, for any soft potential φ(r) characterized by a finite Fourier transform e φ(k), the virial and energy thermodynamic routes are equivalent if the Fourier transform of the total correlation function divided by the density ρ, eh(k)/ρ, is an arbitrary function of ρβ e φ(k), where β is the inverse temperature. This class of approximations includes the mean spherical approximation ...

Solid–liquid equilibria in mixed electrolyte aqueous solution have been investigated using available thermodynamic data for solids and for aqueous electrolyte solutions. The mean spherical approximation (MSA) modified by Lu et al. [Fluid Phase Equilib. 85 (1993) 81] is used to calculate the mean ionic activity coefficients in mixed electrolyte solutions at saturation conditions. Solid–liquid eq...

We have reconsidered the phase behavior of a polydisperse mixture of charged hard spheres (CHSs) introducing the concept of minimal size neutral clusters. We thus take into account ionic association effects observed in charged systems close to the phase boundary where the properties of the system are dominated by the presence of neutral clusters while the amount of free ions or charged clusters...

The analytical solution of the recently proposed ideal chain polymer mean-spherical approximation (Yu.Kalyuzhnyi, Mol.Phys., 94, 735(1998)) is presented for the multicomponent mixture of charged hardsphere linear chain flexible molecules. The solution apply to any mixture of chain molecules with arbitrary distribution of the charge and size of the beads along the molecular backbone. Closed form...

The solution of the associative mean-spherical approximation for iondipolar system is reinvestigated and expressed in terms of only five parameters. Three of them have counterparts in the case without association, and the other two are the monomer fractions of ions and dipoles. The explicit expressions for the thermodynamic quantities are represented in a simpler form. Numerical results for the...

A simple electrolyte in a polar solvent is modelled by a mixture of polar hard spheres and equal diameter charged hard spheres with the possibility of ionic dimerization. The analytical solution of the associative mean spherical approximation (AMSA) for this model is derived to its full extent. Explicit expressions for pair correlation functions and dielectric constant in terms of the AMSA are ...

The thermodynamics of electrolyte solutions has been investigated by many scientists throughout the last century. While several theories have been presented, the most popular models for the electrostatic interactions are based on the Debye− Hückel and mean spherical approximation (MSA) theories. In this paper we investigate the differences between the Debye− Hückel and the MSA theories, and com...